Engineers call for 'artificial trees' to reduce CO2

Constructing a forest of 'artificial trees' is one of the most promising technologies to remove carbon dioxide (CO2) from the atmosphere, according to a report published by the Institution of Mechanical Engineers in the UK. The report also calls for a national UK programme for research and development into "geoengineering" projects that could provide a better understanding of the risks and costs of manipulating the climate.

Most attempts to deal with climate change involve reducing emissions of CO2 and in December the United Nations Convention on Climate Change in Copenhagen will attempt to set binding targets for lowering such emissions for the first time. Yet even an agreement to cut CO2 emission by 50% by 2050 may not be enough to stop the planet's average temperature rising by 2 °C by the end of the century.

Geoengineering – deliberate intervention into the climate system to counteract man-made global warming – offers an alternative approach. The new report, Geoengineering – Giving us Time to Act?, looks at different geoengineering options for tackling climate change, including adding iron to the oceans to produce phytoplankton blooms that then absorb CO2 and constructing giant sunshades in space that can reflect the Sun's rays.

Absorbing carbon

The authors – led by Tim Fox, head of environment and climate change at the Institution of Mechanical Engineers – found that constructing fly-swat-shaped "artificial trees" is the most promising approach to reducing CO2. Such a tree would work by letting air pass through into the structure and then catching the CO2 via a "sorbant" material, such as sodium hydroxide. The CO2 is then removed and buried underground in a similar manner to conventional carbon capture and storage.

According to the report, constructing 100,000 such "trees" – each costing around $20,000 – would require 600 hectares of land but would be enough to remove the CO2 from the UK's homes and transport system.

Algae to the rescue

The report also recommends coating buildings with algae, which would absorb CO2 via photosynthesis. The authors state that the algae can then be "periodically harvested from building surfaces and used as biofuel".

The third recommendation is to make building surfaces more reflective. Although the authors claim that this method may not be as effective as the other two, "it does have the additional benefit of reducing temperatures in city centres, [which] can often be several degrees hotter than the surrounding environment".

The report also outlines a 100 year roadmap for geoengineering in the UK, which calls for £10m per year in funding to help bring together climate scientists, economists and engineers as well as the development and deployment of "smart grids" to manage demand by communicating with electricity meters in homes.

A separate report on geoengineering by the Royal Society is due to be published on Wednesday.

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Energy Harvesting Trees

A British company Solarbotanic has a similar development, except they make natural looking artificial trees that convert light, heat, sound, rain and wind energy into electricity, in addition these trees can capture and store CO2 and other pollutants. At least they look much nicer for our country side

Unlike CCS which only reduces emissions, biochar systems draw down CO2 every energy cycle, closing a circle back to support the soil food web. The "capture" collectors are up and running,PLANTS, the "storage" sink is in operation under our feet, TOP SOIL. Pyrolysis conversion plants are the only infrastructure we need to build out.

Biochar viewed as soil Infrastructure; The old saw;"Feed the Soil Not the Plants" becomes;"Feed, Cloth and House the Soil, utilities included !".Free Carbon Condominiums with carboxyl group fats in the pantry and hydroxyl alcohol in the mini bar.Build it and the Wee-Beasties will come.Microbes like to sit down when they eat.By setting this table we expand husbandry to whole new orders & Kingdoms of life.

This is what I try to get across to Farmers, as to how I feel about the act of returning carbon to the soil. An act of pertinence and thankfulness for the civilization we have created. Farmers are the Soil Sink Bankers, once carbon has a price, they will be laughing all the way to it.

This Congressional Research Service report (by analyst Kelsi Bracmort) is the best short summary I have seen so far - both technical and policy oriented.assets.opencrs.com…R40186_20090203.pdf .

There is real magic coming out of the Asian Biochar conference.15 ear per stalk corn with 250% yield increase,Sacred Trees and chickens raised from near deathMultiple confirmations of 80% - 90% reduction of soil GHG emissions

simple solutions?

Artificial trees vs biochar

Thanks Erich for the biochar links. Good to see real successes. I'm trying to get interest in this in South Africa. But keep this out of the hands of the carbon credits scam - otherwise will get hijacked by fossil fuel interests to support their business as usual at all costs strategy.Using sodium hydroxide to absorb CO2 is just entropically stupid. Sodium hydroxide is produced as co-product in the very energy intensive electrolysis of salt. Engineers - trying to save their jobs? What happened to "cradle to grave" economic accounting? Algae scrubbers for coal fired power stations a better idea as a short term solution while we wean ourselves off fossil fuel energy. Most of teh world still seems to be in denial about the seriousness of climate change and the reality of peak oil and other limits to growth.

People that believe this CO2 garbage must have had a hard time picking out the main sentence of the paragraph in second grade. This is nothing more than a distraction from real environmental issues, and its a HUGE money pit that is only serving to drive down business, suck money from taxpayers, and propagate bad science.

Sodium hydroxide is energetically costly

but alkaline earth orthosilicates -- olivine aka peridot, wollastonite -- are not. Finding cubic myriametres of them is easy, pulverizing the necessary smaller amounts is harder, but not as hard as making and remaking NaOH.

When pulverized Mg2SiO4 sucks down CO2, entropy increases. Thus, mining operations have demonstrated CCS on a far larger scale than artificial trees ever will, and have done so at zero marginal cost and without any forethought on the part of the miners.

Planting trees instead of creating artificial ones seems to be a good idea but the question is, do we have enough room for all these trees we'd need to plant? And I'm afraid the answer is no.But I'm also afraid that these artificial trees will need some energy to be created and will need even more energy to run and that they won't run on solar energy as normal trees do but some energy which produces CO2 on some other place on earth, which will probably beat their purpose. Unless it's nuclear energy, of course.The same goes for algae. Let's let them absorb CO2 for a while, check mark absorbed CO2 quota, then let's use them as biofuel, check mark used biofuels quota and happily release all captured CO2 back to atmosphere.I also wonder how big a house would have to be to produce enough biofuel for just one car running 50 kilometers a day.

CCS

I can't think of a better way to do CCS than to have solar and wind energy stored by a process we have yet to see...Separate carbon from CO2 and create graphite fibre material as a useful by-product. Can anyone offer an educated guess as to how far in the future that kind of process might be?

Sounds good but you need about 1 acre of trees to capture the CO2 from the average car in the UK, that’s about 30 Million acres or 12 million hectares. Now add the same again for the rest of UK transport and double for housing that’s about 50 million hectares of trees or roughly 2 UK’s worth of land, better make them fruit trees so we can eat.Banning cars might solve about a quarter of the problem but I don’t believe that is necessary, but we do need to change our transport technology. An electric car doing about 10,000 miles per year could be powered by 0.05 acres (2sq-m) of ‘current’ best performance solar cells located in a hot sunny place, Sahara? Even allowing 10sq-m per car this would require 30,000 ha or roughly 0.003% of the Sahara. Alternatively it would need about 5,000 5MW off-shore wind turbines. So fundamental to the solution is improved international cooperation, understanding and tolerance.

Geo-engineering

"So fundamental to the solution is improved international cooperation, understanding and tolerance."I largely agree with this statement but the question is how do we get there? The predominant cultural mindset is "economics is God" and it's high priests are economists. Care for others is secondary. The horrendous failure of that system, based on the scientifically untenable notion of no limit to growth, shows just how stupid we really are. Greed and fear rule. Only a change in cultural mindset will lead to wise decisions being made. I'm with James Lovelock that it's too late - we have already started on the slope of a very painful breakdown of "civilisation" as we (the privileged few) know it. As someone said; "Civilisation sounds like a great idea - where can we get some?".

the truth

the human race dose not relize itis the leading force of extinction for plants,animals,and eventualy our selves on this planit. Let me explaine, as the human race evolved we devloped the needs to keep our selfs warm,fed & entertained. with the dvelopment of our cities,towns,& villages we need supplys so we turned to the earth. our earth was once COVERED by vastly conected forests, and over time we have reduced it by half... Globle Warming is a natural cycle it has been going on long before we even existed. By reducing the trees and increasing the co2 emissions we directly increacs this prosses daily. there are things we can do to day to stop thies effects but it is to late. our race has become greedy, power hungry,and above all ignorant as a collective groop. true power lies with in knowledge if the people of the world would open there eyes they would see the true damage they are inflicting we need to teach our children what they need to do to insure there futures. this is not a game we are playing we are dealing with one of the most unique plantes in our solar system,and our galaxie we are the only species like our selfs that we currently know of. I do have one question.

with all of this solar development and renewable energy why are we still dependent on coal & fosel fules and now fake trees ???